package com.itheima.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@Slf4j
@WebFilter("/*")
public class LoginCheckFilter implements Filter {
    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;
        //A. 获取本次请求的URI
        String uri = request.getRequestURI();
        log.info("拦截到请求：{}", uri);
        //B. 判断本次请求, 是否需要登录, 才可以访问

        //定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/user/login",
                "/user/sendMsg",
                "/doc.html",
                "/webjars/**",
                "/swagger-resources",
                "/v2/api-docs"
        };
        Boolean check = check(urls, uri);
        //C. 如果不需要，则直接放行
        if (check) {
            //放行
            filterChain.doFilter(request, response);
            return;
        }
        //D. 判断登录状态，如果已登录，则直接放行
        if (request.getSession().getAttribute("employee") != null) {
            Long empId = (Long) request.getSession().getAttribute("employee");
            //把session中的id传给BaseContext类的setCurrentId方法
            BaseContext.setCurrentId(empId);
            log.info("用户已登录，用户id为：{}", request.getSession().getAttribute("employee"));
            filterChain.doFilter(request, response);
            return;
        }
        //4-2、判断登录状态，如果已登录，则直接放行
        if(request.getSession().getAttribute("user") != null){
            log.info("用户已登录，用户id为：{}",request.getSession().getAttribute("user"));

            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request,response);
            return;
        }
        log.info("用户未登录");
        //E. 如果未登录, 则返回未登录结果,通过输出流方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
    }

    /**
     * 路径匹配，检查本次请求是否需要放行
     *
     * /@param //urls
     * /@param //requestURI
     * /@return
     */
    public Boolean check(String[] urls, String uri) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, uri);
            if (match) {
                return true;
            }
        }
        return false;
    }


}